Multiple criteria decision analysis generally refers to an approach of making numerous and sometimes conflicting evaluations among multiple relations having various uncertainties. Such multiple criteria decision analysis has various applications. One example application is in finding travel deals through an interface from different sources. The interface is configured to access the different sources which have no direct access to each other. Some example sources may include travel search engines (e.g., kayak.com, fly.com, skyscanner.com) and hotel search engines (e.g., trivago.com, room77.com, google.com/hotelfinder). The data at these sources typically are not maintained at one central repository but instead in different databases.